Secondary fuel filter?

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Egregious

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Polly P.
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Monk 36
I've got nearly 80 hours since the PO last changed all fuel filters.* I did replace the Racor 10 micron primaries which looked like they were ready.* The secondaries are Purolator F50149, and there are two of them situated side by side.* It looks like these should be readily available, however I cannot determine the "size" of the filter, i.e. micron size.* I think these should be 2 micron, but I can't tell by searching the current Purolator model F50149.** Also, why are there two of them?* The motors are Perkins 6.354.4.

So far you guys have set me straight on every question, keep up the good work!
 
Usually one is a water sep. and coarse filter , the second finer.

IF you go to a NAPA shop most will have a changeover catalog that shows what is identical, by a different mfg.

You might find filter fineness there , but who cares? If the mfg specked it , it should be OK.

The key to filtering is to have a pair of primaries (usually RACOR) outside the engine room , and really easy to switch over and replace with little effort.

The concept of having a gauge monitor in line and at the instrument panel is fine for inshore boating.
Having the gauge on top of the filter is OK for boats with really clean tanks IF it can be easily monitored a few times a day.

The folks that go out will use the Murphy Gage that shows the inlet AND outlet suction on the same gauge.

This helps when trouble shooting is required.
 
Fred I am not familiar with that Murphy gauge, I'm using a racor vacuum gauge now, maybe I'll replace it with one i have which is equipped with a "telltale" so I can see the high reading at the end of the day.
Please give me some info on the murphy setup.
I'd also like some info or pic. on how the Y strainer after the raw water pump you mentioned a couple of months ago is mounted.
Thanks,
Steve W
 
Google murphy gauges, its in the fuel sectuion.

Sen Dure will download the catalog , its there in 1 inch and 1 1/4 so you should be able to use it on a good sized oulp.

Sen Dure sells them as inlet strainers , look there.
 
10 mics for the primary filter? I have a 6.354 an use 20's. Should I switch?
 
I use 2 micron for the primary (1st) filter in the system, but then my fuel is always pretty clean.
 
This months Pro Boat Builder , on line free! has an opinion by an ex boatyard guy that makes interesting arguments for 30 on the Raycors .

To me it really depends on hoe clean the tanks are , and weather YOU (not the seller) pre filter the fuel as its pumped into your tanks.

A "Baja" filter is a start , as long as your not taking 2 -3 tons of fuel at a fill.
 
I went ahead and ordered replacement filters directly from a Perkins dealer for $4.95 a piece. *I think those are 10 Micron. *Since each engine has two inline that gives me 3 10 micron filters for each engine including the Racor. *So I'm thinking of moving the Racor up to 20 or 30 and getting a converter kit to change the CAV filters to conventional catridges. *I'm thinking this will allow me to change those filters without having to bleed the system (as much?)
 
For my Perkins Sabres I use 30u in Racor primary and Perkins filters on engines. Nary a hiccup. I only bleed the Perkins with the every other year filter changeout. Racors are below the fuel tanks so no bleeding when those are changed out every year. I have never shown any vacuum increase on the Racors. Filter size opening is not as relevant as the beta number.

For a good read on the "enlightened" way to filter fuel, read boatdiesel.com. For*300 to 500 hp newer electronic engines it is the heralded approach.* 30u (bulk filter), 10u and on engine for a 3 filter setup.
 
Woody,
I have the dual Cav set up also on my Lehmans. Mine have never plugged up but I found that an easy way to bleed them is to swap the filters out and then use a newly purchased oil squirt can, filled with clean diesel, to fill the filters through the bleeder bolt at the top of the filter housing. It is common to "roll" the square oring that you can't see when you are replacing it in the top housing so you may want to use a seal pick and a small mirror to confirm it is straight.
The filter will also come with an oring that fits under the washer on the center bolt and also onefor where the filter slips over the center of the top housing. These probably need to be looked at and replaced as well n
 
I have the dual Cav set up

Some of the CAV filters I have worked with had glass sections.

These eventually can crack, and on a gravity setup (the best) will drain the fuel tanks contents into the bilge.
 
Forkliftt wrote:


I have the dual Cav set up also on my Lehmans. ...I found that an easy way to bleed them is to swap the filters out and then use a newly purchased oil squirt can, filled with clean diesel, to fill the filters through the bleeder bolt at the top of the filter housing.
A far easier solution is to get rid of the CAV filter setup altogether and install a pair of the Parker Hamlin spin-on filter adaptors.* These adapter plates mount on the stock CAV filter holder in place of the multi-part, leak-prone CAV cannister filters and allow the use of "normal" spin-ons.* We use Baldwin filters but any properly sized spin-on will work.* You need two kits per engine and they are one of the best improvements you can make to engines like the FL120, Perkins, etc.* We made this change some ten years ago.* A nice thing about using the spin-ons is that you can pre-fill the filters with fuel before putting them on which greatly reduces the bleed time.

*
 
Or just get rid of the CAV filter assembly completely (sell it on E-Bay, lots have been messed up and need replacing) and replace it with a Racor spin-on.
Oh yea, a one liter plastic lab wash bottle works great if you need to prime those CAV's.

-- Edited by Keith on Tuesday 17th of August 2010 02:52:36 PM
 

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Thanks for the replies.* I'm definitely replacing CAV setup, probably going to go with the spin on adapter.* Those things are outboard on my port engine and will be a huge PITA to get at.* Add to that the fact that everyone I have spoken to says bleeding a Perkins is a PITA all by itself.* I really want to avoid all that trouble.
 
Add to that the fact that everyone I have spoken to says bleeding a Perkins is a PITA all by itself.*

Except for me. I think it's cake. Done it many times on a T6.354. Sorry to disappoint you.
 
Engine bleeding , and the ability to do it rapidly and easily may keep the boat off the rocks.

The simplest "ideal" setup is a gravity day tank.

With a gravity tank any air leak becomes a simple to find fuel leak, and priming is simply loostening a few screws and waiting a few seconds.

A surplus aircraft wobble pump will fill the day tank, so loss of electric power will not slow the forward motion.
 
albin man wrote:

Add to that the fact that everyone I have spoken to says bleeding a Perkins is a PITA all by itself.*

Except for me. I think it's cake. Done it many times on a T6.354. Sorry to disappoint you.
My Perkins operator's manual outlines the process.* However, I've seen some documentation that makes it look easy when it isn't really.* I have twin engines so the space can be kinda tight depending on what you're trying to do...

Albin Man, how long did it take you the first time you did it?

*
 
Albin Man, how long did it take you the first time you did it


Gee, I don't remember exactly, maybe 1/2 hour, probably a little less.

After that I did a few things to make it easier. I color coded the bleed screws so they would be very easy to spot in a dark engine room and I tied the proper size wrench to the engine with a lanyard long enough to reach the screw.

And then I would practise when I chenged fuel filters, and I changed every season so I would stay in practise even though the filters didin't need changing that often.

And I had a single engine with some room to work in but always from the top of the engine.

My efforts paid off because my engine shut down 2 times due to fuel clogging (and that's another story for another thread some day).
 
jleonard wrote:




Albin Man, how long did it take you the first time you did it


Gee, I don't remember exactly, maybe 1/2 hour, probably a little less.


*
so I'm looking at 1 hour or more for two motors.* Exactly why I think I should replace the CAV filters with the more easily replaced screw on type filters via the adapter.* So long as I keep the primaries clean which is easy to do I don't think I should have a problem, but possibly cutting that time in half is a great incentive to get rid of the CAV filters as long as that saves the time in the bleeding process.

At any rate I like the idea of color coding and leaving the tools attached since I will need to do it during the installation of the adapters anyway and it might be necessary later on.

I compare the task that*experienced people who say it is "a piece of cake" with some other task like upgrading your computer from Vista to Windows 7.* Anyone who says that is "a piece of cake" might be stretching the truth unless they have a lot of experience -- there are many pitfalls for the inexperienced user.* On a Perkins Diesel I am an inexperienced user so what took some people an hour might take me two while I figure out the gotchas that might seem simple to most experienced users.

However, I'm not afraid to put on my kneepads and get dirty so wish me luck.

Thanks all.

Woody


*
 
I'm curious what has to be done to bleed a Perkins of the type you have.

We have Lehman 120s and the bleeding process is pretty simple. Starting from the rear of the engine you bleed the aft secondary filter, then the forward secondary filter, then the aft bleed screw on the injection pump and then the forward bleed screw on the injection pump. That's pretty much it. There is no need to bleed the injectors themselves.

Is the Perkins significantly different than this?

-- Edited by Marin on Thursday 26th of August 2010 09:14:59 PM
 
Marin,

the Perkins 6.354 are different from your Lehmans in one vital point. The injection pump is a CAV rotary pump where I believe the Lehmans have an inline pump. The rotary pump can be one nasty piece to bleed at times.

Speaking of bleeding the pump, I have never had to bleed the pump when changing filters on my twin 6.354's in the 10 years*I have had the boat.*Wriggle out the old ones, assemble and tighten new ones, open bleed screw on top of filter, manually operate the lift pump until clean fuel squirts out, tighten bleed screw and start.* Never ever had*to bleed the pump doing this.
 
If an engine is a bear to bleed the solution could be at the DD dealer.

They have a hand pump , small & handy that can be either attached to the last filter vent , so all the air can be pulled out,

OR it can be installed before the filters and injection system to push fuel from end to end.

$60 or so.
 
As for micron rating on primary and secondary filters, there was some discussion way back between Bill P and Steve D in PMM.
Bill advocated for a low micron reading on the primaries. His point of view was that the primaries would most likely be positioned on a bulkhead in the ER, where as the secondaries would be mounted on the engine. The easy access primaries could be changed in a hot ER without getting scorched on the engine in heavy seas (been there, done that) where as the secondaries would be tough to change in this situation. *I think Steve D opposed this as the secondaries would be idling as the primaries would be picking up anything that would be coming from the tank. He says you would be better off having the primaries at 20 or 30 micron (picking up the bigger particles) and having the secondaries as per the engine manufacturer specs filtering the finer stuff coming from the tank. This way each filter will be doing what it is best at.
We bought our new (to us) Ocean Alexander 50 in southern Europe and sailed her to Scandinavia this summer. It is more than 2000 nautical miles traversing parts of the Atlantic and North Sea. Not knowing the exact state of the fuel tanks, before setting off I had the fuel system rebuilt with dual Racor 1000's to each engine and 2 micron filter elements. No way would I be crawling between the engine and the fuel tanks in middle of the Bay of Biscay with the boat rocking and rolling and an engine hot from running continuously for tens of hours! (60 hours non-stop from northern Spain to the Channel Islands). I would much rather slip into the ER, turn the valve on the Racors and be going again even before the engines would be so starved of fuel they would stop.
When changing engine lube oil after 1000 nautical miles, I also changed primary fuel filters even if the vacuum needle hardly lifted from the rest position. The filter elements where covered with some black goo but mostly with rust particles.
*
 
r-rossow wrote:
Marin,

the Perkins 6.354 are different from your Lehmans in one vital point. The injection pump is a CAV rotary pump where I believe the Lehmans have an inline pump. The rotary pump can be one nasty piece to bleed at times.


*
All the FL120s I've seen or seen comments about on various boating forums have had the inline injection pump.* CAV/Simms/Minimec (sp?).* But the operators manual for our engines indicates that the FL120 can be fitted with a CAV rotary injection pump and it and its parts are called out in the FL120 operation and service manuals.* But I've not met or corresponded with anyone who actually had one on their FL120.

*
 
Marin wrote:

I'm curious what has to be done to bleed a Perkins of the type you have.

We have Lehman 120s and the bleeding process is pretty simple. Starting from the rear of the engine you bleed the aft secondary filter, then the forward secondary filter, then the aft bleed screw on the injection pump and then the forward bleed screw on the injection pump. That's pretty much it. There is no need to bleed the injectors themselves.

Is the Perkins significantly different than this?

-- Edited by Marin on Thursday 26th of August 2010 09:14:59 PM
Marin
As I recall from three years ago, Bob Smith informed us in his Lehman 120 class that you need to or it is helpful to bleed off the fuel pipes to each injector when re-assembling the pipes...ie if the pipe are ever completely empty of fuel.
I know the manual does not discuss it but I believe we did it in class.

When we wheeled the engine outside and started it up, it cranked up right away.
R.


*
 
I've heard this about bleeding the injectors on the FL120 but I've never done it and never had a startup problem after bleeding. The engine cranks a couple of times and lights off and that's that.

Most of the people I know with FL120s and who service them themselves don't bleed the injectors and say they have the same experience I do. The diesel shop we use doesn't bleed the injectors on an FL120 if the engine needs bleeding after a filter change or being run out of fuel (which I did once).

If installing new injection pipes between the pump and the injector it may be a different story. We've only had that done once when a pipe developed a tiny crack. I wasn't there when the shop installed the new pipe so I don't know if they bled the injector or not. But I can see where it would make sense to do so.
 
When changing* on engine fuel filters on my Perkins Sabres I only use the hand lift pump to fill the filters. I never have to bleed pump or injector lines. It is simple and quick.

-- Edited by sunchaser on Saturday 28th of August 2010 06:21:17 PM

-- Edited by sunchaser on Saturday 28th of August 2010 06:22:23 PM
 
I will try it for myself, and I will let y'all know.
 
"I'm curious what has to be done to bleed a Perkins of the type you have.

We have Lehman 120s and the bleeding process is pretty simple. Starting from the rear of the engine you bleed the aft secondary filter, then the forward secondary filter, then the aft bleed screw on the injection pump and then the forward bleed screw on the injection pump. That's pretty much it. There is no need to bleed the injectors themselves.

Is the Perkins significantly different than this?"

A Perkins is quite a bit easier to bleed than a FL 120 in my experience. Much easier and faster.
Similar proceedure but the Perkins is more forgiving in that it will self bleed to some extent whereas a Lehman will not.
 
The addition of the Parker-Hamilin secondary spin-on adaptors makes a big difference in bleed time on an FL120 after a filter change because you no longer have to fill the filters with the manual lever on the fuel pump. Another thing that helps, at least on our boat, is that we can fill our Racor primaries-- -which are mounted low--- by opening the transfer valve on a saddle tanks. This gravity-feeds fuel into the Racors, which partially empty themselves when the tops are taken off for element changing. So the filters can be filled with fuel right to the top, the lid put on and screwed down, and that's that. There must be some air trapped in the top of the Racor but the engine seems to be able to deal with that as it never stumbles when started up after a filter change.
 

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